Swinging scaffold.



APPLICATION FILED JAN. 3 1'916.

1. G, BARTELL. SWINGING SCAFF'OLD.

Patented June 20, 1916.

J. G. BARTELL.

Patented June 20, 1916.

:faim rfe ZZ,

- folds,

starren srarnsreranr ovrrrCzE JOHN BARTELL, F ST.`AUL, MINNESOTA.

swrneme scarrorn.

adsense.,

aal .wwm t may concern Be it known that I, JOHN G. BARTELL, a citizen of the United States, residing at St.' haul, in the county of Ramsey .and State of Minnesota, have invented a certain new and useful improvement in Swinging Scafowhieh the following `is a speci r'lcation.

This invention pertains to hanging scaffolds, such as are employed in the erection ,of modern buildings, and in cleaning, paintin and repair work.

he objects of the invention are to produce a scaold the deck or platform of *which shall be clear and free from obstrucvtions of any kind; which being made'np of unit sections may be lengthened to any desired extent; which may be raised or lowered at will, and if need be', by a single workman; and which may be permitted to, descend by gravity and at 4:regulated speed, when desired.

l To these ends the invention comn'ises various features, details, and combinations of parts hereinafter described and claimed.

The accompanying drawings illustrate a preferred embodiment of .the invention.

ln these drawings: Figure is a front view ot the suspended scaffold, two complete units or sections and the end .of a third being shown; Fig. 2 is atop plan view oi' one of the transverse metal frames and cablethe planks are attach bands winding mechanisms used at the ends of the sectional units; Fig. 3 1s a top or plan view of the platform seen in Fig. 1;' Fig. 4 .is a

top plan view of a portion' of the transverse frame shown in Fig. 2, the gearing and one cable drum being shown upon a larger scale than in 'said'Fig 2; Fig. 5 is a sectional view of the same parts, taken in the vertical plane of the axis ofthe drum-shaft; Fig. 6 is a transverse section through the 'intermediate or actuating gear of the cable-winding is a View showing the or holding .sateliet Wheel, and oi the ratchet hub of the proximate shaft-rotating gear;

v The scaffold consists primarily of a floor or platform l made up oa series of planks 2 et uniform length and Width, advisedly bound at their .ends with metal straps or 3. to prevent splitting, and to guard against breaking out of lthe-bolts bywhich .frames e.

The ends the planks 2 rest ings.

- though bolts backs of the ratchet teeth and 3, 'and on a .d to the supportingA specification of Leners raient.' Patented Jun@ gq), 19116, ,i .Application filed January 3, 1916. Serial No. 69,860. j v

sidel bars of the metallic frames .4, which bars are preferably formed of angle ir0n. v

members 5 vand end members 6, lthe latter belng of iron or steel plate or of suitable lcasthese parts are, by preference,` securely `and or' other fastening means may loe employed. The members 5 offrames 4 are spaced a suitable distance apart togive adequate room between them for the drums, shaft and gearing, and to permit the planks to extend several planks of adjoining sec.- tlons or umts, space for the actuating lever, and for introduction of the hand for nlation of certain such provision I am enabled t0 locate' the holes for the attaching bolts sufficiently in:

permanently riveted together,

.inches inward past ,said- .members 5,.Wh1lesti ll leaving between the vproximate ends of manip# parts when desired.A By -A Ward from the ends of the planks to prevent breaking out the wood when the `sections-of the scaffold are Arelatively tilted.A

y 7 indicates a shaft' journaled at its ends in the end-plates 6 of frames 4, and c airyingat opposite ends drums 8 and 9. ,'lhisshaft is provided with a longitudinal groove. 10,. which receives inwardlyprojecting splines ofthe drums 8 and 9, or fastening keys lof any usual type. y Adjacent to or formed upon 'a head of drum 9 and rotatable therewith, is

a ratchet `wheel 1l designed topreventnni Winding of the cables l2 from thedrums and 9, the teeth of end of a locking-pawl 13 carried by frame 4.

tion is permitted, thebeveled or inclined neath and lifting vthe pawl 13, which, h ow-` ever, engages with the radial orlabrupt facesf said ratchet being of saw-tootll form and moving beneath the free riding freely be-f.

of. said teeth when thejlrums and ratchet tend to turn in unwinding direction.

To rotate the shaft 7 8 and 9 in cable-Winding direction, there is provided the mechanism shown in Figs. 2 larger scale in Figs. 4, 5,

6 and 7. This comprises two bevel ormiter gears v14 and 15, each provided with a ratchet hub 16, the teeth of which are reversed With reference Wheel 11,

15. VThe intermediate and turn the drums,

to those of ratchet and an intermediate gear 17 which f' Ymeshes at all timesv with .both gears 1li andy gear 17 is provided with a Series of radial Sockets 18, here shown `\1 10 Q incassa as formed in a cruciformyprojection 19 on the inner face of said gear, said sockets serving to receive the end of anactuating lever 20. The gears 14. and 15 are loose on the .shaft 7, and may beI rotated independently thereof, but may be locked to and caused to turn said shaft through the action of pawls 21 and 22 carried by the shaft, or by a sleeve 23 splined or keyed thereto be'- tween gears 14, 15, as seen in Fig. `5. As shown in said Fig. 5, the pawls 21, 22 are each formed with a bent spring leaf or arm, v

and with a thickened head of form alternately to engage and be lifted by the teeth of ratchet hubs 16 of gears 14 and 15, according to thefdirection ofrotation of said gears. The spring-arm of each pawl is at tached to sleeve 23, and the bent form of said arms causes the pawls.vwhen free, to stand out from and clear of the ratchet hubs 16. Normally, the pawls are adjusted to engage the teeth of ratchet hubs 16, such adjustment being effected by nuts or internally threaded bands 21 encircling the correspondngly threaded sleeve 23. By turning said nuts toivard the ratchet hubs 16, the bent arms of the pawls are pressed inwardly until the heads or pawls proper enter into engagement with the teeth of the ratchet hubs, the resilience of the spring-arms being suliicient. however, to permit backward rotation of said hubs, the long inclined backs of the ratchet tee-th then riding beneath and lifting the pawlsyas will be readily understood.` i'

' By backing either nut or band 24:A the pawl which it controls can be freed, and permitted to move outward by reason of the resilience of its spring-arm, to a point beyond the crests of the ratchet teeth. In this way the. gear l-L or 15 with which such paWl coacts will be wholly disengaged from shaft 7. andmade free to oscilla-te thereon when gear 17 .is oscillated by the lever 20. If both pawls be thus freed, the shaft 7 will be. wholly disconnected from both gears 14, 15but will still be held by the locking pawl 13. unless that be manually lifted from the teeth of ratchet wheel 11. The intermediate gear 17 is mounted on a stub-axle 25 carried by a. yoke or frame 26 secured firmly to the frame 4, and having two parallel horizontal arms 26 between which the gearing and sleeve. 23 are confined, as seen in Figs.

-4 and 5.'

Tt is desirable at times to free the drums 8 and 9 and permit the scaffold to descend by" gravity, but it is of course essential that such descent be under perfect control. To this end the' actuating gear 17 is advisa-blyl formed with a llat rim or periphery, as shown in Figs. 4 and 5. and encircled by a brake-lmnd 27 one end of which is made fa st to frame 4 or other fixed support, while the other end is attached to a controlling pawl 13, shaft 7 and drums 8 and 9 will be f made free to rotate, theweight of the scaffold causing'it to descend. This it can do only by unwinding the cables Wound about said drums and thereby turning the drums and shaft 7, which latter turns the pavvlf engaged `gear 14 or 15 and through it the brake-controlled gear 17. When the scaffold has descended sufficiently, pawl 13 thrown into lockingy relation to ratchet 11,

and further descent is prevented. Under this construction and arrangement of parts various manipulations of the ygearing'and drumsv are possible: First. Both pawls 21 being vadjusted to engage their ratchethubs 16, oscillation of hand lever 20 and consequently of gear 17 will cause like oscillation of gears 111 and 15, but in relatively opposite directions. As allthe ratchet hubs 16 have their teeth set to be engaged when the pavvls 21 are moving in a direction to turn the shaft and drums in cable-winding direction, such oscillation of lever '20 will cause rotation of the shaft continuously in one direction, both forward and backward strokes of the lever being effective to yelevate the scadold. Second. By freeing one' pawl 21 and leav `ing the other engaged, onlyone gear 14C or 15 will give motion to the shaft, hence only alternate strokes of the lever-Will be effective. Third'. By releasing the ratchets 16 and 11, the scaffold may be lowered under control of the brake, acting upon gear 17.

It -is obvious that a single -unit section of scaffolding may be employed,.or a number of units'. according to the character and ex tent of the work to be done. Where several units are employed it will be necessary, if the entire platform is to be raised or lowered at once and maintained in horizontal position while so moved, that the several shafts 7 be turned simultaneously vand equally. lt will sometimes happen. however, that not enough hands will be available to attend theseveral levers or brakes, and hence it is desirable. that` the scaffold be capable of elevation or lowering by a single attendant. This is rendered possible by flexibly connecting the ends of sections or units, which may conveniently bc done by using bolts 30 for attacliing the planks 2 to the frames 4, of sufficient length to permit a relative rocking-or tilting movement of the planks and frames. lVith such connection yit is practicable to lower first one end of a section or-unit and then the other, carev being taken not to permit too great linclination -at any time. By working .back and forth from end t0 end of the entire lseries of sections, the Whole scafi fold can/,be brought up to the desired height and made level..

At the extreme ends of the platform, whether of one or of a plurality of sections or units, the planks 2 will extend entirely across the frame 4, which will thus be caused to adord a broad and level bearing for the planks. One ,plank will in such case, be lmade shorter than the rest, in order to give access to the bands or nuts 24, and to permit ready insertion and removal of the actuating lever 20. Each'frame 4 is also provided with a stake-pocket 31 at the outer end-,or it.mayV

be at both ends, to receive stakes or posts 32 upon which to carryI a rope or guard BSL' So far as I amaware no one has heretofore constructed a scaffold platform of units or sections flexibly connected and capable of being .raised or lowered successively, one

.end at a time, so-that the entire platform llowered independently of the other and the several sections be thus raised or lowered successively.

2. A swinging scaffold comprising a platform; transversely extending frames beneath the ends of said platform, each provided with a shaft; drums secured upon said lshaft `to rotate therewith; a ratchet-wheel rotatable with said shaft; a pavvl carried by the frame'and adapted to engage with said ratchet and prevent backwardrotatio'n of the shaft; two mitcr gears loosely encircling said shaft; means carried by said shaft for locking either or both ofsaid gears to the shaft or freeing either or both at will; an intermediate miter gear meshing with the first-mentioned gears; a lever for oscillating they intermediate gear and through it'the gears meshing therewith; and cables windf ing'A about=the drums .and serving to suspend the scaffold.

3. Afscai'old comprising longitudinal oor planks; transverse metallic frames beneath and supporting the ends of said planks, and

containing within themselves cable-Winding 'drums and mechanism for turning said drums in winding direction, said mechanism including anactuating gear provided with sockets to receive an actuating lever, a lever to enter said sockets, and suspending cables winding about said drums; whereby the actuating lever maybe normally removed and the upper surface of the platform lleft entirely free of obstructions.

4. In combination with a platform, transverse supporting frames beneath said platform; and means for lraising or lowering the platform at will, carriedby the respective frames, each such mechanism. comprisn ing a shaft, drums mounted upon and ro tatable with said shaft, suspending cables windingabout said drums, a ratchet Wheel carried by said shaft, a locking pawl engaging with said shaft normally to prevent backward rotation of the shaft' and drums, two miter gears loosely encircling the shaft,

pawls carried by the shaft and serving to engage said gears as the latter are turned, an

intermediate gear constantlymeshing with the first-named gears, a-lever for'oscillating the intermediate gear, a brake-band encircling one of said gears, and a lever for cansing said band to bind upon said gear when the locking pawl is disengaged. to permit descent of the scaffold.

5. The combination with the rotary drum- V shaft, of cablefwinding `mechanism for scaffolding; gears loosely encircling saidv shaft and provided with ratchet hubs, an externally threaded sleeve intermediate said gears and carried by said shaft; spring paw'ls carried by said sleeve and tending normally tov spring clear of the ratchet hubs;

and nuts or xbands -encircling the threaded sleeve, and serving when properly adjusted to press and holdthe pawls in engaging relation to the ratchet hubs. v

In testimony whereof I have signed my naine to this specification.

JOHN Gr. BARTELL. 

